Receptacle unloader



Sept.,2, 1958 w. E. ERICKSON ET AL RECEPTACLE UNLOADER 5 Sheets-Sheet 1Filed Nov. 21

Sept. 2, 1958 w. E. ERICKSON ET AL 2,350,185

RECEPTACLE UNLOADER Filed Nov; 21, 195e- V 5 Sheets-Sheet 2 Sept. '2,1958 w. E. ERl'cKsoN ETAL RECEPTACLE UNLOADER 5 Sheets-Sheet 3 FiledNov. 21, 1956 Sept. 2; 1958 w. E. ERICKSON ET AL 2,850,185

RECEPTACLE UNLOADER Filed' Nov. 21, 1956 s Sheets-Sheet 4 p 8 w. E.ERICKSON ET AL 2,850,185

RECEPTACLE UNLOADER 5 SheetsSheet 5 Filed Nov. 21, 1956 RECEPTACLEUNLQADER Willard Erickson, (Ihicago, and Albert Musschoot,

Park Ridge, lib, assignors to Link-Bait Company, a corporation ofIllinois Application November 21, 1956, Serial No. 623,744

4 Claims. (Cl. 214-53) This invention relates to new and usefulimprovements in apparatus for causing material positioned in areceptacle on opposite sides of a given location to move in oppositedirections toward said location, and deals more particularly withapparatus for oscillating a railway car in such a manner as tosimultaneously discharge material from the opposite end portions of thecar through its side door opening.

It has been found that material positioned in the opposite longitudinalportions of a railway car Will be moved in opposite directions toward aside door opening with a positive conveying action when the car ispositioned on a base, the opposite end portions of which are supportedfor oscillation by oppositely inclined arms. When so supported, thefloor of the car moves in a manner corresponding to that of theconnecting rod of a four-bar linkage having nonparallel rocker arms ofequal length. The oscillating movements of the base are limited so thatan acute angle will always be maintained between each arm and theportion of the base between the arms.

Considering the movement of the base more specifically, it is a combinedlongitudinal reciprocation and tilting of the base alternately inopposite directions. In other words, as the base moves toward one endposition of its longitudinal movement it is tilted in one direction andas it moves toward the opposite end position it is tilted in theopposite direction.

It is the primary object of this invention to provide apparatus forimparting movement to material positioned in the two half portions of arailway car, or other receptacle, in opposite directions relative to alocation intermediate said portions, the apparatus being driven in sucha mannerv as to impart identical conveying movements to the two portionsof the car or receptacle.

A further important object of the invention is to provide apparatus forimparting combined reciprocatory and alternately oppositely directedtilting movements to a car or other receptacle, the motion impartingportion of-said apparatus being so designed as to minimize the startingload on the prime mover therefor When the apparatus is set intooperation.

Still another object of the invention is to provide a drive. employingsynchronously operated unbalanced shafts for applying forces tooscillate a railway car or other receptacle and to cause material in tworelatively horiz ontally positioned portions thereof to move in oppositedirections toward a location intermediate said portions.

Other objects and advantages of the invention will be apparent duringthe course of the following description.

In the accompanying drawings forming a part of this specification and inwhich like reference characters are employed to designate like partsthroughout the same,

Figure 1 is a side elevational view of apparatus embodying theinvention,

Figure 2 is a diagrammatic view illustrating a type of linkage that isincorporated in the structure illustrated in Fatented Sept- 2, 1958 iceFigure 3 is an enlarged vertical sectional view taken on line 3-3 ofFig. 1,

Figure 4 is an enlarged fragmentary end elevational lg 6W of the driveemployed by the device illustrated in ig. 1, F Figure 5 is a top planview of the drive illustrated in Figure 6 is a transverse verticalsectional view taken on line 6-6 of Fig. 4, and

Figure 7 is a longitudinal vertical sectional view taken on line 7-7 ofFig. 5.

In the drawings, wherein for the purpose of illustration is shown thepreferred embodiment of the invention, and first particularly referringto Fig. 1, reference character 8 designates a box car that has beenmoved onto rails 9 carried by a movable base or platform 11. The box car8 is centered on the base 11 between clamping devices 12 which aremounted for movement into engagement with the couplers 13 to restrainthe car from movement on the base, as will be later described. It willbe noted that one of the rails 9 is mounted on the base 11 at a greaterelevation than the other rail so that the car 8 is supported in alaterally tilted position, as is best illustratedin Fig. 3.

The base 11 spans a shallow pit 14 and is supported for movement by arms15 which are pivotally mounted in the bottom of the. pit 14 and extendupwardly and outwardly toward opposite end portions of the car 8 forpivotal connection to the base 11. The base 11 is urged or biased intoits neutral position, at which the arms 15 lie at equal and oppositeangles with the base, by spring assemblies 16 which are arranged toapply forces to the opposite end portions of the base in directionssubstantially normal to the arms 15.

At the opposite ends of the pit 14, jacks 17 are provided for engagingthe bottom of the base 11 to support the latter against verticalmovement during movement of the car 8 thereon.

Centered longitudinally of the base 11 is a drive 18 for impartingmovement to the base 11. This drive is mounted on the underside of thebase 11 and is actuated by a drive motor 19.

Referring now to Figs. 1 and 3 for a detail description of the arms 15and the manner in which they support the base 11 in the pit 14, it willbe seen that two spaced pairs of bearings 20 are mounted in transversealignment on a weldment 21 beneath each end portion of the base 11 forpivotally supporting the shafts 22 at the lower ends of the arms. Eacharm 15 is formed of two laterally spaced links 23 which are integralwith a longitudinal web 24 and with a bushing 25 at each end portion ofthe arm. The bushing 25 at the lower end of each arm 15 is mounted on aportion of its associated shaft 22 which extends between and issupported for angular movement by the bearings 20. The two arms 15associated with each of the wel'dments 21 extend upwardlyand outwardlytoward the adjacent end of the base 11. The upper ends of these arms areconnected to the base 11 by shafts 27 which extend through the bushings25 at the upper ends of the arms and have their laterally extending endportions mounted for angular movement in spaced pairs of bearings 28that are mounted on the bottom of the base 11.

It will be noted that each weldment 21 is provided with a standard 29,the top of which lies in closely spaced relation-ship with the bottom ofthe base 11 so that the latter may be supported thereon duringinstallation, replacement :or repair of the arms 15 or spring assemblies16.

As illustrated in Fig. 1, the jack 17 at each end of the pit 14 isformed of a toggle linkage 31 which is operated by a hydraulic motor 32for vertical movement into and out of engagement with the bottom of theassociated end portion of the base 11.

The clamping devices 12 are illustrated in their inoperative positionsby broken lines in Fig. 1. When so positioned, the clamping devices liewithin recesses 33 at the opposite ends of the pit 14 and are entirelybelow the level of the rails 9 so that cars 8 may be moved onto and offof the base 11 in any suitable manner. After a car 8 has been positionedon the base 11', however, the two clamping devices 12 are pivotedupwardly and moved longitudinally of the tracks 34 at opposite ends ofthe base 11 and into their operative positions by hydraulic cylindertype fluid motors 35. Each of the two fluid motors 35 is mounted toextend longitudinally of the base 11 and has its operating rod 36pivotally connected to the associated clamping device 12 by a pin 37, asillustrated in Figs. 1 and 3.

It will be readily apparent that controlled, simultaneous operation ofthe two fluid motors 35 will permit centering of the car 8 on the base11 between the clamping devices 12. Further, the continued applicationof fluid pressure to the motors 35 will maintain the devices 12 in tightclamping engagement with the couplings 13 to prevent any longitudinalmovement of the car 8 on the base 11.

Referring now to Figs. 4 to 7, inclusive, for a detail description ofthe drive 18, it will be seen that it includes a pair of spaced parallelshafts 38 which extend transversely of and are rotatably supported onthe bottoms of the opposite sides of the base 11 by bearings 39. Asillustrated in Fig. 1, the two shafts 38 are centered longitudinally ofthe base 11 and are connected for synchronized rotation in oppositedirections by the meshing gears 41 which are of the same diameter andhave the same number of teeth. These gears are keyed to correspondingend portions of the shafts at one side of the base 11. Rotation of oneof the gears will produce rotation of the other at the same speed but inan opposite direction as illustrated by the arrows of Fig 7. The twogears 41 are substantially completely enclosed by the housing 43 whichis suspended on the side of the frame 11 by a bracket 44 at the top andby brackets 45 at opposite ends of the housing.

' At the opposite side of the base 11 from the housing 43, one of theshafts 38 has keyed thereon a drive sprocket 46 which is connected by achain 47, or the like, to the sprocket 48 of the drive motor 19.Operation of the motor 19, therefore, will cause the sprocket 46 torotate its associated shaft 38 and gear 41 which in turn will rotate thesecond gear 41 and its associated shaft 38 in the opposite direction.

Rigidly mounted in axially spaced relationship on each of the two shafts38 are a pair of discs 49 which have mounted on the inwardly facingsurfaces thereof a pair of arcuate retaining flanges 51. The flanges 51associated with each pair of discs 49 are aligned axially of the shaft38 upon which the discs are mounted, and a plurality of weights 52extend between and are rigidly connected to the inner faces of the discsradially inwardly of the inner surfaces of the flanges 51. The weights52, therefore, provide an eccentrically arranged or unbalancedcounterweight for each of the two shafts 38. It will be noted, however,that the gears 41 connect the two shafts 38 in such a manner that theweights 52 are positioned above and below their respective shafts, asviewed in Fig. 7. In other words, when one set of weights 52 ispositioned below its shaft, the other set of weights 52 will bepositioned above its shaft. Rotation of the two shafts 38 in oppositedirections, therefore, will position the weights 52 horizontally oncorresponding sides of their associated shafts 38 so that the directionsof eccentricity of the weights coincide in both directionslongitudinally of the base.

Referring now to Figs. 1 and 2 for a detail description of the operationof the device, the car 8, loaded with grain or other flowable solidmaterial, is moved onto the base 11 and approximately centered in anysuitable manner. During this movement of the car 8, the clamping devices12 will be in their inoperative positions in the recesses 33, as shownby broken lines in Fig. 1, and the jacks 17 will be in their elevatedpositions to support the base against vertical movement. The fluidmotors 35 are thereafter actuated by the admission of pressure fluidthereto to cause the clamping devices 12 to move into engagement withthe couplers 13 of the car 8 and to center the car on the base 11 whereit will be restrained against further movement relative to the base. Itwill be noted at this point that the rails adjacent the ends of the pit14 are arranged at the same difference of elevation as that of the rails9 so that the car 8 will be laterally tilted as it moves onto the base11 and will be righted as it is removed from the base.

After the car 8 has been properly positioned and clamped on the base 11,the fluid motors 32 are actuated to lower the jacks 17 so that the base11 is supported for movement on the arms 15. The base is urged into abalanced or horizontal position, however, by the action of the springassemblies 16 During or after the above described clamping and jacklowering operations, the door of the car 8 is opened so that a portionof the material adjacent the opening will spill into the materialreceiving hopper 53.

The drive motor 19 is then energized to rotate the two shafts 38 and theeccentrically positioned weights 52. It will be noted at this time thatany initial movement of one shaft 38 which elevates its weights 52 isaccompanied by a movement of the other shaft to lower its weights. Inother words, the starting load on the drive motor 19 is maintained at aminimum by the counterbalancing effect of the weights 52 of each shafton the weights of the other shaft. Because of the eccentric arrangementof the weights 52, oppositely rotating forces will be developed by theunbalanced action of the weights and these forces will be applied to thebase 11 to effect movement of the latter. Any movement of the base 11,however, is opposed by the spring assemblies 16 to the extent that theforces exerted on the base by the spring assemblies at opposite endsthereof are unbalanced. In other words, movement of the base 11 ineither direction from its neutral or balanced position is opposed by thespring assemblies 16 at one end of the base and assisted by those at theother end of the base and the difference between the spring forces isapplied to the base in a direction tending to return the base to itsbalanced position. The inertia forces developed at the extremes of eachoscillation of the base 11, car 8 and its contents at a given speed ofrotation of the shafts 38 are substantially balanced by the differencebetween the spring forces. Thus, a relatively small total forcedeveloped by the eccentrically arranged weights 52 will produceoscillations of suflicient amplitude to cause the contents of the car 8to be conveyed to and discharged through the center door opening.

Considering now the manner in which the rotating shafts 38 and theirassociated weights 52 develop and apply the oscillation producing forcesto the base 11, it will first be noted that the directions ofeccentricity of the weights 52 from theirassociated shafts are inagreement only in opposite horizontal directions. The forces developedby the rotating weights 52, therefore, are additive, and at a maximumvalue, only in the two opposite directions longitudinally of the base11. This maximum force condition will be developed in both directionsalong the base during each revolution of the shafts 38. In other words,each revolution of the shafts 38 will produce one complete vibration oroscillation of the base. Of course, the opposite directions of rotationof the shafts will eliminate any dissimilarity in the oscillatorymovements of the base 11 in opposite directions.

It might also be noted at this time that the directions of applicationof the forces to the base 11 by the shafts 38 relative to the directionsof eccentricity of the Weights 52 on their shafts will depend upon thespeed of rotation of the shafts. More specifically, when the shafts 38are rotated at speeds below the natural vibration frequency of thesystem comprised of base 11 and spring 16 the forces applied to the base11 will agree in direction with the directions of eccentricity of theweights 52 from their associated shafts. At speeds above the naturalvibration frequency of the above mentioned sys tem, however, each shaft38 and its associated weights 52 will tend to rotate about a spin axispassing through their combined center of gravity so that the forcesapplied to the base 11 by the shaft will be in a direction opposite thedirection of eccentricity of the weights from their associated shaft. Ineither event, however, the speed of rotation of the shafts 38 will equalthe operating frequency or the frequency of forced vibration of the base11.

The car 8 being supported by and held in a relatively fixed position onthe base 11 will move with the base and the material within the car willalso, to some extent, move with the car and base. The material, car 8and base 11, therefore, form a resiliently supported body having anatural vibration frequency which will vary in accordance with theweight of the material in the car. Movement of the material within thecar 8 will have a dampening effect upon the free vibration of thematerial, car and base 11, however, so as to limit the amplitude ofvibration during temporary operation at the natural frequency.Ordinarily, however, the speed of notation of the shafts 38 is broughtup immediately after starting to an operating frequency which exceedsthe natural frequency of the material, car 8 and base 11. During theacceleration of the operating frequency through the natural frequency, ashort period of resonant frequency operation will occur but due to thepreviously mentioned dampening effect of the material, this short periodof resonant frequency operation will have no harmful effects.

The vibrations or oscillations imparted to the base 11 and the car 8thereon by the shafts 38 and their associated weights 52 will impart apositive conveying action to the material in the opposite end portionsof the car to move the material from both end portions toward the doorof the car. Additionally, the tilted position of the car will cause thematerial to flow toward the lower side thereof so that the material willspill from the door opening into the material receiving hopper 53.

This conveying action of the car body, and primarily its floor, upon thematerial in the opposite end portions of the car 8 can best be explainedby reference to Fig. 2, in which the connecting rod 11a, the fixed link14a and the rocker arms 15:; correspond to the base 11, the floor of thepit 14 and the supporting arms 15 of the structure illustrated in Fig.l. The arms 15a are of equal length and are arranged in nonparallelrelationship while the length of the connecting rod 11a is greater thanthe distance between the pivotal connections of the arms 15a and thefixed link 14a. Similarly, the portion of the base 11 between itspivotal connections to the upper ends of the arms 15 is greater than thespacing between the pivotal mountings of the arms on the bottom of thepit 14. It will be appreciated that the extent of movement of theconnecting rod 11a between its extreme positions A and B has beenexaggerated to more clearly illustrate the principle of operation of thedevice.

As illustrated in Fig. 2, the point of pivotal connection between eachof the rocker arms 15a and the connecting rod 11a moves upwardly andinwardly along an inclined arcuate path as the point of pivotalconnection between the other arm and the connecting rod moves downwardlyalong an oppositely inclined arcuate path when the arms are oscillatedrelative to the fixed link 14a. Of course, the directions of movement ofthe points of pivotal connection are reversed during successive strokesof each oscillation. As the connecting rod moves in either directionaway from, and is subsequently returned to, its position C of equalangularity with the rocker arms 15a, it is tilted downwardly in thedirection of its movement and returned to its horizontal position,respectively. It will be readily apparent that movements of the base 11must correspond with those of the connecting rod 11a and that themovements of the floor of the car 8 will substantially conform to thoseof the base 11.

Considering first the movements of the right hand end portion of the car8, as viewed in Fig. 1, and the movements of this end portion of the carfloor from the position A of the connecting rod 11a to the position B ofthe connecting rod, it will be seen by reference to Fig. 2 that thematerial supported by the floor, and to a limited extent by the lowertilted side wall of this portion of the car, will move with the car andwill be given a component of movement which is inclined upwardly andlongitudinally inwardly from its initial position toward a fixedlocation near the middle of the car. When, however, the direction ofmovement of the car floor is reversed for its return to position A, thetrajectory of the mass of material in this end portion of the car 8 willcause it to continue its movement longitudinally inwardly from itsinitial position but relative to the car and to fall back into supportedrelation relative to the car floor at a point nearer the door than thatfrom which it was initially projected. At approximately the same timethat the material has returned into supported relation relative to thecar floor, it will again be subjected to the conveying acti-on describedabove. In other words, alternate movements of this end portion of thecar 8 from position A to position B and from position B back to positionA will cause the material to be moved first with the car and thenrelative to the car but substantially continuously toward a fixedlocation near the middle of the car.

As clearly illustrated in Fig. 2, the opposite end portion of the car 8will be moved in the same manner as the first described end portion butin an oppositely inclined direction and with a phase diiference of onehundred and eighty degrees so that the material therein will besubjected to an identical but oppositely directed con-- veying actionduring alternate strokes of operation. Since the material in both endportions of the car 8 moves substantially continuously and in oppositedirections relative to a fixed location near the middle of the car,there appears to be simultaneous movement of the material in the two endportions toward the car door. Of course, the flowable nature of thematerial being unloaded will prevent the entire mass of the materialfrom moving by increments away from the opposite ends of the car 8. Thepositive conveying action imparted to the car 8, however, will cause thematerial to flow out of the open door quickly and will effect a completeremoval of the material from the car. The tilted condition of the car 8facilitates the discharge of the material through the door opening.

It is to be understood that the form of this invention herewith shownand described is to be taken as a preferred example of the same, andthat various changes in the shape, size, and arrangement of parts may beresorted to without departing from the spirit of the invention or thescope of the subjoined claims.

Having thus described the invention, we claim:

1. A device for moving material in opposite end portions of a railwaycar in opposite directions toward the middle portion of the car fordischarge through a contrally located side wall opening, comprising anelongated base having rails mounted thereon for receiving a railway car,means for retaining said car at a central position upon said base formovement with said base, means supporting said base for alternatelyoppositely directed plane motion having translational and rotationalcomponents such that the base is movable alternately in oppositelongitudinal directions and during successive longitudinal movements ispivoted in opposite directions about its transverse center line, andmeans for oscillating said base upon said supporting means comprising apair of unbalanced shafts mounted on said base for rotation aboutparallel axes spaced longitudinally of said base and extendingtransversely thereof, and means for rotating said shafts in oppositedirections and at synchronized speeds with the directions of unbalanceof the shafts coinciding in both directions longitudinally of said base.

2. A device for moving material in opposite end portions of a railwaycar in opposite directions toward the middle portion of the car fordischarge through a centrally located side wall opening, comprising anelongated base having rails mounted thereon for receiving a railway car,means for retaining said car at a central position upon said base formovement with said base, means supporting said base for alternatelyoppositely directed plane motion having translational and rotationalcomponents such that the base is movable alternately in oppositelongitudinal directions and during successive longitudinal movements ispivoted in opposite directions about its transverse center line, andmeans for oscillating said base upon said supporting means comprising apair of unbalanced shafts mounted on said base for rotation aboutparallel axes spaced longitudinally of said base and extendingtransversely thereof, means drivingly connecting said shafts forsynchronized rotations in opposite directions with the directions ofunbalance of the shafts in phase in both directions longitudinally ofsaid base, and a prime mover mounted on said base for jointly rotatingsaid shafts, whereby the unbalanced condition of the rotating shaftscauses said shafts to apply alternately oppositely directed longitudinalforces to said base.

3. A device for moving material in opposite end portions of a railwaycar in opposite directions toward the middle portion of the car fordischarge through a centrally located side wall opening, comprising anelongated base having rails mounted thereon for receiving a railway car,means for retaining said car at a central position upon said base formovement with said base, means supporting said base for alternatelyoppositely directed plane motion having translational and rotationalcomponents such that said base is movable alternately in oppositelongitudinal directions and during successive longitudinal movements ispivoted in opposite directions about its transverse center line, andmeans for oscillating said base upon said supporting means comprising apair of parallel shafts spaced longitudinally and extending transverselyof said base for rotation relative thereto about axes symmetricallydisposed on either side of the transverse center line of said base,means drivingly connecting said shafts for synchronized rotation inopposite directions, a weight eccentrically mounted on each of saidshafts, said Weights being equal and their directions of eccentricitycoinciding longitudinally of said base, and drive means mounted on saidbase for rotating said shafts.

4. A device for moving material in opposite end portions of a railwaycar in opposite directions toward the middle portion of the car fordischarge through a centrally located side wall opening, comprising anelongated base having rails mounted thereon for receiving a railway car,means for retaining said car at a central position upon said base formovement with said base, means supporting said base for alternatelyoppositely directed plane motion having translational and rotationalcomponents such that the base is movable alternately in oppositelongitudinal directions and during successive longitudinal movements ispivoted in opposite directions about its transverse center line, andmeans for oscillating said base upon its supporting means comprising apair of unbalanced shafts rotatably mounted on said base for rotationabout axes symmetrically disposed upon either side of the transversecenter line of said base and aligned with the translational component ofmotion of said base, a pair of gears having equal diameters rigidlymounted on said shafts in meshed relationship with each other forsynchronized rotation in opposite directions with the directions ofunbalance of said shafts coinciding in both directions of alignment withthe translational component of movement of said base, and a motormounted upon said base and drivingly connected to one of said shafts forrotating said shafts.

References Cited in the file of this patent UNITED STATES PATENTS2,200,724 Robins May 14, 1940 2,266,594 Ertel Dec. 16, 1941

